DNA From Discarded Gum Leads to Conviction in 1980 Oregon Murder

In the long run, it was a discarded piece of chewing gum, casually spit on the bottom in 2021, that was the important thing to fixing the cold-case homicide of a faculty pupil that had confounded the authorities in Oregon for greater than 4 a long time.

Robert Arthur Plympton had been below police surveillance because the authorities decided that yr that he was a “probably contributor” to a DNA profile developed from swabs taken from the physique of Barbara Mae Tucker, who was 19 when she was murdered on the Mount Hood Neighborhood Faculty campus in 1980.

On Friday, Mr. Plympton, 60, was discovered responsible of murdering Ms. Tucker after a three-week bench trial in Portland, Ore. Based on The Oregonian, which reported on the investigation and Mr. Plympton’s conviction, it was the oldest cold-case murder in Gresham, Ore., east of Portland.

On the evening of Jan. 15, 1980, Ms. Tucker was anticipated at a category on the school, the place she was learning enterprise. She by no means arrived.

College students on their approach to class the following morning discovered her “partially clad” physique on a shrub-covered slope close to a campus car parking zone, The Oregonian reported on the time. There have been indicators that Ms. Tucker had been sexually assaulted, and that she had struggled along with her assailant.

For many years, the authorities have been unable to determine a suspect or make an arrest.

Step one towards a breakthrough within the case got here in 2000, when vaginal swabs that had been taken throughout Ms. Tucker’s post-mortem have been despatched to the Oregon State Police Crime Lab for evaluation. Lab technicians have been then in a position to develop a DNA profile from the swabs.

In 2021, Parabon NanoLabs, a Virginia firm whose providers embrace DNA-based forensics, recognized Mr. Plympton as “a probable contributor to the unknown DNA profile developed in 2000,” the Multnomah County district lawyer’s workplace stated in an announcement. It was not clear how the DNA connection was made; the district lawyer’s workplace didn’t instantly reply to a request for touch upon Tuesday.

Detectives with the Gresham Police Division discovered that Mr. Plympton was residing in Troutdale, Ore., east of Portland and northeast of Gresham, and started surreptitiously watching him, prosecutors stated.

When investigators noticed Mr. Plympton spit a bit of chewing gum onto the bottom, they collected it and submitted it to a state police crime lab, prosecutors stated.

“The lab decided the DNA profile developed from the chewing gum matched the DNA profile developed from Ms. Tucker’s vaginal swabs,” the district lawyer’s workplace stated.

Mr. Plympton was arrested on June 8, 2021, as he was driving away from the Troutdale house he shared along with his spouse and son, The Oregonian reported.

He had a felony document, together with a conviction for second-degree kidnapping in Multnomah County in 1985, in accordance with the Oregon Division of Corrections.

Mr. Plympton was 16 when Ms. Tucker was murdered. Witnesses reported seeing her with a person the evening she was killed, and a number of other folks reported seeing her run into the road waving her arms, maybe making an attempt to flag somebody down for assist, The Oregonian reported.

Kirsten Snowden, the Multnomah County chief deputy district lawyer, stated on the trial that there was no proof that Ms. Tucker and Mr. Plympton had recognized one another, in accordance with The Oregonian.

Mr. Plympton’s lawyer, Stephen Houze, stated on the trial that there was “unmistakable, unavoidable cheap doubt” about who killed Ms. Tucker, in accordance with The Oregonian. He stated that witnesses had described the person who was seen with Ms. Tucker — who was almost six ft tall — as being about her top or taller, however Mr. Plympton was nearer to 5-foot-8. He additionally stated investigators by no means examined Ms. Tucker’s clothes for DNA proof.

“We’ll enchantment, and we’re assured that his convictions will likely be overturned,” Mr. Houze and his regulation accomplice Jacob Houze stated in an announcement on Tuesday.

Decide Amy Baggio of Multnomah County Circuit Court docket discovered Mr. Plympton responsible of 1 depend of first-degree homicide, and 4 counts of “completely different theories of homicide within the second diploma,” in accordance with the district lawyer’s workplace.

“To be clear, this court docket has zero doubt by any means that Robert Plympton beat Barbara Tucker in her head and face till she died,” she stated on the trial. “He did.”

Decide Baggio didn’t discover Mr. Plympton responsible of sexual assault, saying that prosecutors had didn’t show past an affordable doubt that he had assaulted Ms. Tucker whereas she was nonetheless alive, The Oregonian reported.

Mr. Plympton is scheduled to be sentenced on June 21. Based mostly on his age on the time of Ms. Tucker’s loss of life, he faces a life sentence with the potential of parole after 30 years on the first-degree homicide cost.

Two members of Ms. Tucker’s household wept and embraced after the decision was introduced, in accordance with The Oregonian. Ms. Tucker’s older sister, Alice Juan, stated in an announcement on Tuesday that her household was “thrilled that this was lastly solved.”

“I believed it may not be because the years went on, however Barbie was a particular little woman,” she stated. Her little sister, she added, “was shiny, bubbly, caring, all of these issues.”

Kitty Bennett contributed analysis.